Prosthetic valve with improved washout

ABSTRACT

Described embodiments are directed toward prosthetic valves having a support structure and at least one leaflets. The leaflet comprises means for allowing fluid that is behind the leaflet to pass through to the front of the leaflet when the leaflet is not in the closed position. The prosthetic valve includes a leaflet moveable between an open position that permits antegrade flow through the prosthetic valve and a closed position that prevents regurgitant flow through the prosthetic valve, the leaflet having an aperture or gap, or a separation of portions of the leaflet to allow a flow or exchange of fluid between a front and back of the leaflet, when the leaflet is not in the closed position.

FIELD

The present disclosure relates generally to prosthetic valves and morespecifically flexible leaflet-type prosthetic heart valve devices.

BACKGROUND

Prosthetic valves are used to replace natural valves in a cardiovascularsystem when the natural valve no longer functions properly. A flexibleleaflet prosthetic valve comprises one or more leaflets that move underthe influence of fluid pressure.

Prosthetic leaflets are attached to a support structure to form a valve.In operation, the flexible leaflets open when the inflow fluid pressureexceeds the outflow fluid pressure and close when the inflow fluidpressure drops below the outflow fluid pressure. The free edges of theleaflets coapt under the influence of outflow fluid pressure closing thevalve to prevent outflow blood from flowing retrograde through thevalve. FIGS. 1A and 1B are perspective and axial views, respectively, ofa closed prosthetic valve 10 that includes a frame 20 that supportsleaflets 30, in accordance to what is known in the art. The closedprosthetic valve 10 represents when the outflow pressure downstream ofthe prosthetic valve 10 is greater than the inflow pressure upstream ofthe prosthetic valve 10, wherein the leaflets 30 close to preventregurgitant flow through the prosthetic valve 10.

FIGS. 1C and 1D are a perspective view and axial view, respectively, ofthe prosthetic valve 10 where the leaflets 30 are open such as when theinflow pressure upstream of the prosthetic valve 10 is greater than theoutflow pressure, wherein the leaflets 30 open to allow fluid to proceedin the forward flow direction 402 through the prosthetic valve 100.

FIGS. 1E and 1F are cross-sectional views of the closed prosthetic valve10 of FIG. 1B along cutline 1E-1E and the open prosthetic valve 10 ofFIG. 1D along cut line 1F-1F, respectively. FIG. 1E shows the retrogradeflow direction 404 where the outflow pressure of the prosthetic valve 10is greater than the inflow pressure thus closing the leaflet 30. FIG. 1Fshows the fluid moving in the forward flow direction 402 through theprosthetic valve 10 where the inflow pressure is greater than theoutflow pressure thus opening the flexible leaflet 30 away from thevalve axis X. Behind the leaflet 30 the fluid follows a recirculatingdirection, referred to as recirculating flow 406, including flow in theretrograde flow direction 404 between the leaflet 30 and a structurebehind the leaflet 30, such as, but not limited to, the frame 20, aprosthetic conduit, and native tissue.

The lack of or insufficient fluid in the retrograde flow direction 404or recirculating flow 406 can result in the fluid flow slowing orstagnating behind the leaflet 30 and in particular, at the leaflet base308 where the leaflet 30 intersects the frame 20. The slowing orstagnation of fluid flow is known to cause the blood to clot and formthrombus. Thrombus is detrimental in that it can hinder the leaflet 30opening and closing dynamics which in turn leads to increased pressuregradients that negatively affect valve performance. Thrombus may alsoflow downstream which can lead to stroke, heart attack or pulmonaryembolism.

There remains a need for a prosthetic valve that reduces or eliminatesthe reduced or stagnated flow behind an open prosthetic valve leaflet.

SUMMARY

Described embodiments are directed to apparatus, system, and methods forvalve replacement, such as cardiac valve replacement. More specifically,described embodiments are directed toward flexible leaflet valve deviceshaving biological or synthetic leaflet material and a support structure,and methods of making and implanting the valve devices.

According to one example (Example 1), a valve having a leaflet moveablebetween an open position that permits antegrade flow through theprosthetic valve and a closed position that prevents regurgitant flowthrough the prosthetic valve, the leaflet comprising an aperture or gap,or a separation of portions of the leaflet to allow a flow or exchangeof fluid between the front and back of the leaflet, when the leaflet isnot in the closed position.

According to another example (Example 2), further to Example 1, theaperture, gap or separation is operable to close to prevent flow ofexchange of fluid between the back and the front of the leaflet, whenthe leaflet is in the closed position.

According to another example (Example 3), further to Examples 1 or 2,comprising a support structure, wherein the leaflet is coupled to thesupport structure.

According to another example (Example 4), further to of Examples 1-3,the leaflet includes a first leaflet component and a second leafletcomponent.

According to another example (Example 5), further to Example 4, thefirst leaflet component is upstream of the second leaflet component, orwherein the first leaflet component is downstream of the second leafletcomponent.

According to another example (Example 6), further to Examples 4 or 5,said flow or exchange of fluid is via an aperture, gap or separation ofthe first and second components, when the leaflet is not in the closedposition.

According to another example (Example 7), further to any one of Examples4 to 6, and in accordance with Example 1, the second leaflet componentcomprises an inflow free edge; and defines a gap between the secondleaflet component and the support structure.

According to another example (Example 8), further to any one of Examples4 to 7, the first leaflet component or the second leaflet componentdefines an aperture therethrough; and wherein the other of the firstleaflet component or the second leaflet component is operable to occludethe aperture.

According to another example (Example 9), further to any one of Examples4 to 8, the first leaflet component and the second leaflet componentpartially overlap.

According to another example (Example 10), further to Example 9, thefirst leaflet component comprises a first overlap region and the secondleaflet component comprises a second overlap region; wherein the firstand second overlap regions are in sealing engagement with one another,when the leaflet is in the closed position.

According to another example (Example 11), further to Example 10, thefirst and second overlap regions each extend from a free edge of therespective first and second leaflet component.

According to another example (Example 12), further to Example 11, thefirst overlap region extends from an outflow free edge of the firstleaflet component and the second overlap region extends from an inflowfree edge of the second leaflet component.

According to another example (Example 13), further to any one ofExamples 10 or 11, the first leaflet component comprises apertures inthe first overlap region, or wherein the second leaflet componentcomprises apertures in the second overlap region.

According to another example (Example 14), further to any one ofExamples 4 to 13, the first leaflet component is stationary relative tothe second leaflet component, or vice versa.

According to another example (Example 15), further to any one ofExamples 4 to 13, and in accordance with Example 3, the first leafletcomponent, or the second leaflet component is stationary relative to thesupport structure.

According to another example (Example 16), further to any one ofExamples 4 to 13, the first leaflet component is configured to move moreslowly than the second leaflet component.

According to another example (Example 17), further to Example 16, thefirst leaflet component has a higher bending stiffness than the secondleaflet component.

According to another example (Example 18), further to any one ofExamples 16 or 17, the first leaflet component is upstream of the secondleaflet component.

According to another example (Example 19), further to any one ofExamples 4 to 13, the second leaflet component is configured to movemore slowly than the first leaflet component.

According to another example (Example 20), further to Example 19, thesecond leaflet component has a higher bending stiffness than the firstleaflet component.

According to another example (Example 21), further to any one ofExamples 19 or 20, the second leaflet component is upstream of the firstleaflet component.

According to another example (Example 22), further to any one ofExamples 9 to 21, and in accordance with Example 3, the first and secondleaflet components overlap and define an overlap region which tapers inwidth towards the support structure.

According to another example (Example 23), further to Example 22, whenthe leaflet is in the closed position, there is a regurgitant gap orgaps of a predetermined size between the first and second leafletcomponents, extending away from the support structure.

According to another example (Example 24), further to any one ofExamples 1-23, the leaflet comprises multiple apertures, gaps orseparations of portions of the leaflet, to allow a flow or exchange offluid between the front and back of the leaflet, when the leaflet is notin the closed position.

According to another example (Example 25), further to any one ofExamples 4 to 23, the leaflet comprises multiple first leafletcomponents and/or wherein the leaflet comprises a first leafletcomponent comprising multiple outflow free edges.

According to another example (Example 26), further to Example 25,further includes a tether element which couples the multiple firstleaflets or multiple outflow free edges to tether element may preventprolapse.

According to another example (Example 27), further to any one ofExamples 25 or 26, in further of example 3, the second leaflet componentcomprises multiple inflow free edges, defining multiple gaps between thesecond leaflet component and the support structure, corresponding to oneof the said multiple first leaflet components or outflow free edges.

According to another example (Example 28), further to any one ofExamples 24 to 26, the second leaflet component defines multipleapertures therethrough, wherein the first leaflet component is operableto occlude the apertures, or wherein one said multiple first leafletcomponents is operable to occlude each said aperture.

According to another example (Example 29), further to any one ofExamples 1-28, wherein the shape of the shape of the leaflet, and, andin further of Example 3, the shape of a corresponding attachment regionto a support structure, is generally that of a parabola or of anisosceles trapezoid.

According to another example (Example 30), further to any one ofExamples 1-23, the leaflet comprises a porous polymer membrane and amaterial present in pores of the porous polymer membrane such that theor each leaflet is impermeable.

According to another example (Example 31), further to Examples 30, theporous polymer membrane is expanded polytetrafluoroethylene.

According to another example (Example 32), further to any one ofExamples 30 or 31, the material present in the pores is an elastomer oran elastomeric material or a non-elastomeric material.

According to another example (Example 33), further to any one ofExamples 30 to 32, the material present in the pores is a TFE/PMVEcopolymer.

According to another example (Example 34), further to any one ofExamples 1-33, the leaflet comprises a biological tissue.

According to another example (Example 35), further to any one ofExamples 30 to 34, the leaflet comprises when in further of any one ofExamples 4 to 13, wherein the or each first leaflet component and/or thesecond leaflet component comprises said porous polymer membrane and amaterial present in pores of the porous polymer membrane such that theor each first leaflet component and/or the second leaflet component isimpermeable.

According to another example (Example 36), further to Example 35,wherein at least one of the first leaflet component and the secondleaflet component comprises a biological tissue.

According to another example (Example 37), further to any one ofExamples 1-36, the leaflet is coupled to a support structure in the formof a frame.

According to another example (Example 38), further to Example 38, theframe defines a generally open pattern of apertures operable to allowthe frame to be compressed and expanded between different diameters.

According to another example (Example 39), further to any one ofExamples 1 to 38, comprising a plurality of leaflets.

According to another example (Example 40), further to Example 39,comprising valve may comprise three leaflets.

According to another example (Example 41), further to any one ofExamples 39 or 40, wherein each leaflet comprises a leaflet free edge,wherein leaflet free edges may coapt under the influence of retrogradefluid pressure; thereby closing the valve.

According to another example (Example 42), further to any one ofExamples 1 to 41, wherein the valve is a prosthetic valve.

According to another example (Example 43), further to Examples 42,wherein the prosthetic valve is a prosthetic heart valve.

The foregoing Examples are just that, and should not be read to limit orotherwise narrow the scope of any of the inventive concepts otherwiseprovided by the instant disclosure.

According to another example (Example 44), a method of making aprosthetic valve, comprising: obtaining a support structure such as aleaflet frame or conduit, obtaining a leaflet including a first leafletcomponent and a second leaflet component; coupling the first leafletcomponent adjacent to an inlet portion of the support structure; andcoupling the second leaflet component adjacent to an outlet portion ofthe support structure such that a second overlap region of a secondinflow free edge of the second leaflet component overlaps a firstoverlap region of a first outflow free edge of the first leafletcomponent such that a portion of a second inflow side of the secondleaflet component is in contact and in sealing engagement with a portionof a first outflow side of the first leaflet component when the leafletis in a closed position defining a leaflet overlap region preventingfluid flow through a lumen in a retrograde direction, and wherein thefirst overlap region and the second overlap region are not in contacttherewith wherein the first outflow free edge and the second inflow freeedge define a gap therebetween when the leaflet is not in the closedposition, wherein fluid adjacent a second outflow side can pass throughthe gap during fluid flow in a forward direction.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a furtherunderstanding of the present disclosure and are incorporated in andconstitute a part of this specification, illustrate embodimentsdescribed herein, and together with the description serve to explain theprinciples discussed in this disclosure.

FIG. 1A is a perspective view of a closed prosthetic valve that includesa frame that supports leaflets, in accordance to what is known in theart;

FIG. 1B is an axial view of the closed prosthetic valve of FIG. 1A thatincludes a frame that supports leaflets, in accordance to what is knownin the art;

FIG. 1C is a perspective view of the prosthetic valve of FIG. 1A wherethe leaflets are open such as when the inflow pressure upstream of theprosthetic valve is greater than the outflow pressure, in accordance towhat is known in the art;

FIG. 1D is an axial view of the prosthetic valve of FIG. 1C where theleaflets are open such as when the outflow pressure upstream of theprosthetic valve is greater than the outflow pressure, wherein theleaflets open to allow forward flow through the prosthetic valve, inaccordance to what is known in the art;

FIG. 1E is a cross-sectional view of the closed valve of FIG. 1B alongcutline 1E-1E, in accordance to what is known in the art;

FIG. 1F is a cross-sectional view of the open valve of FIG. 1D alongcutline 1F-1F, in accordance to what is known in the art;

FIG. 2A is a perspective view of a prosthetic valve in a closedposition, in accordance with an embodiment;

FIG. 2B is an axial view of the prosthetic valve of FIG. 2A in a closedposition, in accordance with an embodiment;

FIG. 2C is a perspective view of the prosthetic valve of FIG. 2A in anopen position, in accordance with an embodiment;

FIG. 2D is an axial view of the prosthetic valve FIG. 2C in an openposition, in accordance with an embodiment;

FIG. 2E is a cross-sectional view of the closed valve of FIG. 2B alongcutline 2E-2E, in accordance with an embodiment;

FIG. 2F is a cross-sectional view of the open valve of FIG. 2D alongcutline 2F-2F, in accordance with an embodiment;

FIG. 3A is perspective view of a prosthetic valve, in accordance withanother embodiment;

FIG. 3B is an axial view of the prosthetic valve of FIG. 3A in a closedposition, in accordance with an embodiment;

FIG. 3C is a perspective view of the prosthetic valve of FIG. 3A in anopen position, in accordance with an embodiment;

FIG. 3D is an axial view of the prosthetic valve FIG. 3C in an openposition, in accordance with an embodiment;

FIG. 3E is a cross-sectional view of the closed valve of FIG. 3B alongcutline 3E-3E, in accordance with an embodiment;

FIG. 3F is a cross-sectional view of the open valve of FIG. 3D alongcutline 3F-3F, in accordance with an embodiment;

FIG. 4A is perspective view of a prosthetic valve, in accordance withanother embodiment;

FIG. 4B is an axial view of the prosthetic valve of FIG. 4A in a closedposition, in accordance with an embodiment;

FIG. 4C is a perspective view of the prosthetic valve of FIG. 4A in anopen position, in accordance with an embodiment;

FIG. 4D is an axial view of the prosthetic valve FIG. 4C in an openposition, in accordance with an embodiment;

FIG. 4E is a cross-sectional view of the closed valve of FIG. 4B alongcutline 4E-4E, in accordance with an embodiment;

FIG. 4F is a cross-sectional view of the open valve of FIG. 4D alongcutline 4F-4F, in accordance with an embodiment;

FIG. 5 is a perspective view of a prosthetic valve wherein the leafletoverlap region has a non-uniform width, in accordance with anembodiment;

FIG. 6A is a perspective view of a prosthetic valve having a frame and aplurality of leaflets each having a first leaflet component and a secondleaflet component defining a shape substantially that of an isoscelestrapezoid, in accordance with an embodiment;

FIG. 6B is a perspective view of a prosthetic valve having a frame and aplurality of leaflets each having a first leaflet component and a secondleaflet component defining a shape substantially that of an isoscelestrapezoid, in accordance with an embodiment;

FIG. 7 is a plan view of the frame of the embodiment of FIGS. 6A and 6Bunrolled to a flat profile;

FIG. 8 is a plan view of a leaflet pattern comprising a plurality offirst leaflet components and second leaflet components, in accordancewith an embodiment;

FIG. 9 is a plan view of a leaflet pattern comprising a plurality offirst leaflet components, in accordance with an embodiment;

FIG. 10 is a plan view of a leaflet pattern comprising a plurality ofsecond leaflet components, in accordance with an embodiment;

FIG. 11A is a perspective view a prosthetic valve having a frame and aplurality of leaflets each having a plurality of first leafletcomponents that overlap the second inflow side of a second leafletcomponent, in accordance with an embodiment;

FIG. 11B is a perspective view a prosthetic valve having a frame and aplurality of leaflets each having a plurality of first leafletcomponents that overlap the second outflow side of a second leafletcomponent, in accordance with another embodiment;

FIG. 11C is a cross-sectional view along cut-line 110 of the embodimentof FIG. 11B when the leaflet is in the closed position;

FIG. 11D is a cross-sectional view along cut-line 110 of the embodimentof FIG. 11B when the leaflet is in the open position;

FIG. 12A is a plan view of a leaflet pattern comprising a plurality offirst leaflet components, in accordance with an embodiment;

FIG. 12B is a plan view of a leaflet pattern comprising a plurality offirst leaflet components, in accordance with an embodiment;

FIG. 12C is a plan view of a leaflet pattern comprising a plurality offirst leaflet components, in accordance with an embodiment;

FIG. 13 is a plan view of a leaflet pattern comprising a plurality ofsecond leaflet components, in accordance with an embodiment;

FIG. 14 is a prosthetic valve with a second leaflet component with arelatively narrow strip that attaches as the base of the frame, inaccordance with an embodiment;

FIG. 15 is another prosthetic valve similar to the embodiment of FIG. 14that includes one first leaflet component that overlaps both secondinflow free edges, in accordance with another embodiment;

FIG. 16A is perspective view of a prosthetic valve, in accordance withanother embodiment;

FIG. 16B is an axial view of the prosthetic valve of FIG. 16A in aclosed position, in accordance with an embodiment;

FIG. 16C is a perspective view of the prosthetic valve of FIG. 16A in anopen position, in accordance with an embodiment;

FIG. 16D is an axial view of the prosthetic valve FIG. 16C in an openposition, in accordance with an embodiment;

FIG. 16E is a cross-sectional view of the closed valve of FIG. 16B alongcutline 16E-16E, in accordance with an embodiment;

FIG. 16F is a cross-sectional view of the open valve of FIG. 16D alongcutline 16F-16F, in accordance with an embodiment.

DETAILED DESCRIPTION

Persons skilled in the art will readily appreciate that various aspectsof the present disclosure can be realized by any number of methods andapparatus configured to perform the intended functions. Stateddifferently, other methods and apparatus can be incorporated herein toperform the intended functions. It should also be noted that theaccompanying drawing figures referred to herein are not necessarilydrawn to scale, but may be exaggerated to illustrate various aspects ofthe present disclosure, and in that regard, the drawing figures shouldnot be construed as limiting.

Although the embodiments herein may be described in connection withvarious principles and beliefs, the described embodiments should not bebound by theory. For example, embodiments are described herein inconnection with prosthetic valves, more specifically cardiac prostheticvalves. However, embodiments within the scope of this disclosure can beapplied toward any valve or mechanism of similar structure and/orfunction. Furthermore, embodiments within the scope of this disclosurecan be applied in non-cardiac applications.

The term “leaflet” as used herein in the context of prosthetic valves isa flexible component of a one-way valve wherein the leaflet is operableto move between an open and closed position under the influence of apressure differential. In an open position, the leaflet allows blood toflow through the valve. In a closed position, the leaflet substantiallyblocks retrograde flow from passing through the valve. In embodimentscomprising multiple leaflets, each leaflet cooperates with at least oneneighboring leaflet to block the retrograde flow from becomingregurgitant. The pressure differential in the blood is caused, forexample, by the contraction of a ventricle or atrium of the heart, orthe drainage of blood from the ventricle or atrium. As the pressure onthe inflow side of the valve rises above the pressure on the outflowside of the valve, the leaflets are caused to open and blood flowstherethrough. As blood flows through the valve into a neighboringchamber or blood vessel, the pressure on the inflow side equalizes withthe pressure on the outflow side. As the pressure on the inflow side ofthe valve drops below the pressure on the outflow side of the valve, theleaflets are caused to return to the closed position generallypreventing regurgitant flow of blood through the valve.

As used herein, “inflow fluid pressure” refers to a fluid pressure at anupstream location of the valve. “Outflow fluid pressure” refers to afluid pressure at a downstream location of the valve.

As used herein, “retrograde” and “retrograde flow” refers to fluid flowat a downstream location of the valve that is moving toward the valve.Retrograde flow may be encountered, by way of example, but not limitedto, in turbulent or recirculatory flow that is downstream of the valve,and during the pressure transition of the inflow fluid pressure droppingbelow the outflow fluid pressure tending to change the flow pattern awayfrom a forward flow direction.

As used herein, “regurgitant”, “regurgitation”, and “regurgitant flow”refers to flow through a valve when the leaflets are in the closeposition. A valve that is exhibiting regurgitation is commonly said tobe leaking. Regurgitant flow is differentiated from retrograde flow inthat regurgitant flow is fluid flow that passes through the valve from adownstream location to an upstream location whereas retrograde flow isflow in a downstream location that does not necessarily pass through thevalve.

The term “biocompatible material” as used herein generically refers toany material with biocompatible characteristics including synthetic,such as, but not limited to, a biocompatible polymer, or a biologicalmaterial, such as, but not limited to, human, bovine, and pig tissue.

The terms “native valve” orifice and “tissue orifice” refer to ananatomical structure into which a prosthetic valve can be placed. Suchanatomical structure includes, but is not limited to, a location whereina cardiac valve may have been surgically removed. It is understood thatother anatomical structures that can receive a prosthetic valve include,but are not limited to, veins, arteries, ducts and shunts. It is furtherunderstood that a valve orifice or implant site may also refer to alocation in a synthetic or biological conduit that may receive a valve.

As used herein, “couple” means to join, connect, attach, adhere, affix,or bond, whether directly or indirectly, and whether permanently ortemporarily.

Embodiments herein include various apparatus, systems, and methods for aprosthetic valve, such as, but not limited to, cardiac valve replacementdevices. The valve is operable as a one-way valve wherein the valvedefines a valve orifice into which one or more flexible leaflets open topermit flow and close so as to occlude the valve orifice and preventregurgitant flow in response to a differential fluid pressure. Inaccordance with embodiments, the leaflet is configured so as to increasethe motion of fluid behind an open leaflet so as, but not limited to,reducing the likelihood of fluid stagnation and potential thrombusformation behind the open leaflet.

In accordance with embodiments, each of the one or more flexibleleaflets comprise a means for allowing a flow or exchange of fluidbetween the front and back of the leaflet when the leaflet is not in theclosed position through the leaflet via an aperture, gap or separationof portions of the leaflet. This flow or exchange of fluid may includefluid from in front of the leaflet passing through the leaflet to theback of the leaflet which displaces the existing fluid that is behindthe leaflet and keeps that fluid in motion. This exchange of fluid mayalso include fluid from behind the leaflet passing through the leafletto the front of the leaflet which displaces the existing fluid that isbehind the leaflet and keeps it in motion.

In accordance with embodiments, a prosthetic valve includes at least oneleaflet and a support structure supporting the leaflet so that it mayoperate as a one-way valve. As described in the embodiments presentedbelow, the support structure is described as a frame and used herein asan example, and used interchangeably with support structure. It isunderstood that other support structures are anticipated, including, butnot limited to, conduits, that are operable to support the leaflet forits intended function.

FIGS. 2A and 2B are perspective and axial views, respectively, of aprosthetic valve 100 in a closed position, in accordance with anembodiment. FIGS. 2C and 2D are perspective and axial views,respectively, of the prosthetic valve 100 in an open position, inaccordance with an embodiment. FIGS. 2E and 2F are cross-sectional viewsof the closed prosthetic valve 100 of FIG. 2B along cutline 2E-2E and ofthe prosthetic valve 100 of FIG. 2D along cutline 2F-2F, respectively.

Frame

As shown in FIG. 2A, a frame 200 is operable to hold and support aplurality of leaflets 300. The frame 200 is annular, that is, it definesa cylinder having a lumen 214 having an axis X and a plurality ofcommissure posts 210 extending parallel to the axis X that are spacedfrom one another. Between the commissure posts 210 is a leafletattachment region 212 that is operable to couple with and support theleaflet 300 about a perimeter of the leaflet 300 except for a leafletfree edge 306.

The frame 200 defines a cylinder having a frame inner side 202 and aframe outer side 204 opposite the frame inner side 202. The frame 200further defines a plurality of commissure posts 210.

Although the frame 200 in the instant embodiment defines a cylinder ofconstant diameter along the axis X, it is understood that the diametermay vary along the axis X. Such variation may be advantageous, such as,but not limited to, to better fit the anatomy of the tissue orifice andadjacent upstream and downstream anatomy. Similarly, the frame 200 maynot necessarily be circular along the axis X but, by way of example, butnot limited thereto, may be oval and lobed. Such variation may beadvantageous, such as, but not limited to, to better fit the anatomy ofthe tissue orifice and adjacent upstream and downstream anatomy, and/orto control the flow dynamics through the valve and around the leaflets.

In accordance with an embodiment, the frame 200 is annular about acentral longitudinal axis X of the prosthetic valve 100 as shown inFIGS. 2A-2D. The frame 200 has an inflow end 206 and an outflow end 208opposite the inflow end 206 and defines a lumen 110 therebetween alongan axis X. The frame 200 has at least one leaflet attachment region 212for each leaflet 300. The leaflet attachment region 212 has an inflowportion 232 and an outflow portion 234.

The frame 200 can be etched, cut, laser cut, stamped, three-dimensionalprinted, among other suitable processes, into an annular structure or asheet of material, with the sheet then formed into an annular structure.Wires and strands may also be used to form into an annular structure.

The frame 200 can comprise, such as, but not limited to, any metallic orpolymeric material that is generally biocompatible. The frame 200 cancomprise a shape-memory material, such as Nitinol, a nickel-titaniumalloy. Other materials suitable for the frame 200 include, but notlimited to, other titanium alloys, stainless steel, cobalt-nickel alloy,polypropylene, acetyl homopolymer, acetyl copolymer, other alloys orpolymers, elastomers and elastomeric materials, other shape memoryand/or superelastic materials, polymers, and composite materials, or anyother material that is generally biocompatible having adequate physicaland mechanical properties to function as a leaflet frame 200 asdescribed herein. Suitable frames can be made from a variety ofmaterials and need only be biocompatible or able to be madebiocompatible.

It is appreciated that FIG. 2A shows a frame 200 that is operable to beused in a surgical procedure, wherein the frame 200 has a fixed diameterboth pre- and post-implant. It is appreciated that the frame 200 may beconfigured for use in a transcatheter procedure, wherein the frame 200can be expanded from a smaller pre-deployment diameter to a largerdeployed diameter.

A wide variety of frames are known in the medical technology arts, andany suitable frame can be utilized. One requirement is that the frameprovide a surface to which the leaflet can be attached and function asdescribed herein.

As described below, in accordance with an embodiment, the frame hasradially compressed and radially expanded configurations. Such a framecan be implanted at a point of treatment within a body vessel byminimally invasive techniques, such as delivery and deployment with anintravascular catheter. The frame can optionally provide additionalfunction to the medical device. For example, the frame can provide astenting function, i.e., exert a radially outward force on the interiorwall of a vessel in which the medical device is implanted. By includinga frame that exerts such a force, a medical device according to theinvention can provide both a stenting and a valving function at a pointof treatment within a body vessel.

The stent art provides numerous frames acceptable for use in the presentinvention, and any suitable stent can be used as the frame. The specificframe chosen will depend on numerous factors, including the body vesselin which the medical device is being implanted, the axial length of thetreatment site within the vessel, the number of valves desired in themedical device, the inner diameter of the vessel, the delivery methodfor placing the medical device, and other considerations. Those skilledin the art can determine an appropriate frame based on these and otherconsiderations.

The frame can be self-expandable or balloon expandable. The structuralcharacteristics of both of these types of frames are known in the art,and are not detailed herein. Each type of frame has advantages and forany given application, one type may be more desirable than the otherbased on a variety of considerations. For example, in the peripheralvasculature, vessels are generally more compliant and typicallyexperience dramatic changes in their cross-sectional shape duringroutine activity. Medical devices for implantation in the peripheralvasculature should retain a degree of flexibility to accommodate thesechanges of the vasculature. Accordingly, medical devices according tothe invention intended for implantation in the peripheral vasculature,such as prosthetic venous valves, advantageously include aself-expandable frame. These frames, as is known in the art, aregenerally more flexible than balloon-expandable frames followingdeployment.

Suitable frames can also have a variety of shapes and configurations,including being comprised of wire, strands, braided strands, helicallywound strands, ring members, consecutively attached ring members,zig-zag members, tubular members, and frames cut from solid tubes andflat sheets. Frames may define a generally open pattern of aperturesoperable to allow the frame to be compressed and expanded betweendifferent diameters, in accordance with embodiments.

Leaflet

As shown in FIGS. 2A-2F, the leaflet 300 is coupled to each of the atleast one leaflet attachment region 212 of the frame 200.

The leaflet 300 includes a first leaflet component 310 and a secondleaflet component 320, in accordance with an embodiment. The firstleaflet component 310 has a first inflow side 312 and a first outflowside 314 opposite the first inflow side 312 that defines a firstthickness. The term “inflow side” is that side which is facing theinflow end 206 of the frame 200 when the leaflet 300 is in the closedposition. The term “outflow side” is that side which is facing theoutflow end 208 of the frame 200 when the leaflet 300 is in the closedposition. The first leaflet component 310 has a first frame attachmentedge 319 and a first outflow free edge 316.

The second leaflet component 320 has a second inflow side 322 and asecond outflow side 324 opposite the second inflow side 322 defining asecond thickness. The second leaflet component 320 has a plurality ofsecond frame attachment edges 329, a second inflow free edge 327 and asecond outflow free edge 326 opposite the second inflow free edge 327.The second leaflet component 320 is configured to be movable between anopen position to allow fluid flow in a forward flow direction throughthe lumen 214 and a closed position in cooperative engagement with thefirst leaflet component 310 that prevents regurgitant flow.

The first frame attachment edge 319 of the first leaflet component 310is coupled to the inflow portion 232 of the leaflet attachment region212 with the first inflow side 312 facing the axis X. The inflow portion232 is that portion adjacent to the inflow end 206 of the frame 200.

The second frame attachment edges 329 of the second leaflet component320 is coupled to the outflow portion 234 of the leaflet attachmentregion 212 with the second inflow side 322 facing the axis X. Theoutflow portion 234 is that portion adjacent to the outflow end 208 ofthe frame 200.

The first leaflet component 310 and the second leaflet component arearranged on the frame 200 such that they at least partially overlap. Asecond overlap region 325 adjacent to the second inflow free edge 327overlaps a first overlap region 315 adjacent to the first outflow freeedge 316 such that a portion of the second inflow side 322 of the secondleaflet component 320 is in contact and in sealing engagement with aportion of the first outflow side 314 of the first leaflet component 310when the leaflet 300 is in the closed position defining a leafletoverlap region 335 operable to prevent regurgitant flow through theleaflet 300 at the leaflet overlap region 335, as shown in FIG. 2E.

During fluid flow in the forward flow direction 402 when the leaflet 300is not in the closed position, as shown in FIG. 2F, when the inflowpressure is greater than the outflow pressure, the first overlap region315 and the second overlap region 325 move away from each other whereinthe first outflow free edge 316 and the second inflow free edge 327define a gap 330 therebetween. The gap 330 formed between the firstleaflet component 310 and the second leaflet component 320 when theleaflet 300 is not in the closed position allows fluid adjacent thefirst outflow side 314 and the second outflow side 324 to pass throughthe gap 330 when the fluid is moving in the forward flow direction 402through the lumen 214. That is, recirculating flow 406 from behind theleaflet 300 may pass through the gap 330 preventing the recirculatingflow 406 from stagnating behind the leaflet 300. Further, the gap 330also allows fluid flow in the forward flow direction 402 to pass throughthe gap 330 from the first inflow side 312 and the second inflow side322 further disrupting and displacing the recirculating flow 406 behindthe leaflet 300 to downstream of the leaflet 300. Thus, blood behind theleaflet 300 is less likely to clot or form thrombus, particularly at theleaflet base 308 and where it attaches to the frame 200.

In accordance with an embodiment, the first leaflet component 310 isstationary relative to the second leaflet component 320 such that thegap 330 may be formed between the second leaflet component 320 movingaway from the first leaflet component 310 under fluid pressure duringfluid flow in the forward flow direction 402.

In accordance with another embodiment, the first leaflet component 310has a bending stiffness that is greater than the second leafletcomponent 320 such that the second leaflet component 320 may move morequickly relative to the first leaflet component 310 such that the gap330 may be formed between the second leaflet component 320 moving awayfrom the first leaflet component 310 under fluid pressure during fluidflow in the forward flow direction 402. Examples of providing apredetermined bending stiffness include, but not limited to, using amaterial having a predetermined modulus and providing a component ofpredetermined thickness.

In accordance with another embodiment, FIGS. 3A and 3B are perspectiveand axial views, respectively, of a prosthetic valve 100 in a closedposition. FIGS. 3C and 3D are perspective and axial views, respectively,of the prosthetic valve 100 in an open position, in accordance with theembodiment of FIGS. 3A and 3B. FIGS. 3E and 3F are cross-sectional viewsof the closed prosthetic valve 100 of FIG. 3B along cutline 3E-3E and ofthe prosthetic valve 100 of FIG. 3D along cutline 3F-3F, respectively.The first overlap region 315 comprises a plurality of apertures 350extending from the first inflow side 312 to the first outflow side 314operable to allow upstream flow to pass through the apertures 350 fromthe first inflow side 312 to the first outflow side 314 during fluidflow in the forward flow direction 402 when the leaflet 300 is not inthe closed position. The apertures 350 in the first overlap region 315provides, in part, that the first leaflet component 310 moves to theopen position at a slower rate than the second leaflet component 320ensuring that the gap 330 is formed therebetween. During retrogradeflow, the second overlap region 325 is in sealing engagement with theapertures 350 when the leaflet 300 is in the closed position preventingfluid flow through the apertures 350 in the retrograde flow direction404. Leakage of the fluid when the leaflet 300 is closed is known asregurgitation, or regurgitent flow.

In accordance with another embodiment, FIGS. 4A and 4B are perspectiveand axial views, respectively, of a prosthetic valve 100 in a closedposition. FIGS. 4C and 4D are perspective and axial views, respectively,of the prosthetic valve 100 in an open position, in accordance with theembodiment of FIGS. 4A and 4B. FIGS. 4E and 4F are cross-sectional viewsof the closed prosthetic valve 100 of FIG. 3B along cutline 4E-4E and ofthe prosthetic valve 100 of FIG. 4D along cutline 4F-4F, respectively.The second overlap region 325 comprises a plurality of apertures 350extending from the second inflow side 322 to the second outflow side 324operable to allow fluid adjacent the second outflow side 324 to passthrough the apertures 350 from the second outflow side 324 to the secondinflow side 322 during fluid flow when the leaflet 300 is not in theclosed position.

The apertures 350 in the second overlap region 325, in part, augmentsthe benefit of the gap 330 to further allow the flow of the fluidadjacent the second outflow side 324 to pass to the second inflow side322. During reverse flow, the second overlap region 325 is in sealingengagement with the apertures 350 when the leaflet 300 is in the closedposition preventing fluid flow through the apertures 350 in theretrograde flow direction 404, preventing regurgitation.

In the embodiments of FIGS. 2A, 3A, and 4A, the leaflet overlap region335 has a relatively uniform width. The first overlap region 315 and thesecond overlap region 325 defines a leaflet overlap region 335 that isrelatively consistent in width from adjacent the frame 200 to away fromthe frame 200. FIG. 5 is a perspective view of a prosthetic valve 100wherein the leaflet overlap region 335 has a non-uniform width, inaccordance with an embodiment. In the embodiment of FIG. 5, the firstoverlap region 315 and the second overlap region 325 defines a leafletoverlap region 335 that tapers in width from a minimum adjacent theframe 200 to a maximum farthest away from the frame 200. As shown inFIG. 5, the leaflet overlap region 335 defines a width and a length,wherein the width has a non-uniform dimension along the width as definedby the first outflow free edge 316 having a concave profile. It isunderstood that the width of the overlap region 335, as defined by thedegree of overlap between first overlap region 315 and the secondoverlap region 325 is predetermined for, among other things, to preventprolapse of the second inflow free edge 327 and to ensure a sufficientsealing engagement between the first overlap region 315 and the secondoverlap region 325 when the leaflet 300 is in the closed position toprevent regurgitant flow due to downstream fluid pressure. Under certaindownstream fluid pressure conditions, the first overlap region 315 andthe second overlap region 325 may slip relative to each other with thepotential of slipping out of engagement, or prolapsing, if the overlapregion 335 is not sufficiently wide. It is understood that the frame 200and/or the leaflet 300 will elastically deform under fluid pressure.Further, it is understood that the elastic deformation at the firstoutflow free edge 316 and the second inflow free edge 327 may be greateraway from the attachment point to the frame 200. Therefore, the width ofthe overlap region 325 is predetermined to accommodate for the increasein deformation further away from the support provided by the frame 200.

As will be described later in reference to the embodiment of FIG. 6B,the first overlap region 315 and the second overlap region 325 define aleaflet overlap region 335 that tapers in width such that there is nooverlap between the first leaflet component 310 and the second leafletcomponent 320 adjacent to and a predetermined distance away from theframe 200 which defines a regurgitant gap 331 of a predetermined size.

It is also understood that the degree of overlap between first overlapregion 315 and the second overlap region 325 will also affect the sizeof the gap 330 and the degree of separation between the first outflowfree edge 316 and the second inflow free edge 327 when the leaflet 300is not in the closed position.

The relative size of the first leaflet component 310 and the secondleaflet component 320 is predetermined for a particular purpose. Inaccordance with an embodiment, the first leaflet component 310 is maderelatively small so as to not excessively extend into the lumen 214 ofthe frame 200, particularly if the first leaflet component 310 isrelatively inflexible, so as to minimize the impediment to flow in theforward flow direction 402 through the prosthetic valve 100 when in theopen position. It is understood that the relative size of the firstleaflet component 310 and the second leaflet component 320 willdetermine, in part, the characteristics of the pattern of flow in theforward flow direction 402 and the pattern of flow in the recirculatingdirection, that is, recirculating flow 406, which will also, in part,determine the dynamics of the first leaflet component 310 and the secondleaflet component 320. It has been found in some embodiments that as thefirst leaflet component 310 extends further into the lumen 214, thesecond leaflet component 320 may begin to flutter when in the openposition during forward flow conditions.

Related to the relative size of the first leaflet component 310 and thesecond leaflet component 320 is the axial location X1 of the overlapregion 335 relative to the upstream-most location of the leaflet base308. In general, wherein the axial location X1 increases away from theinflow end 206 and closer to the outflow end 208, the first leafletcomponent 310 will extend further into the lumen 214 of the frame 200and thus affect the characteristics of the flow in the forward flowdirection 402.

The shape of the leaflets 300 are defined, at least in part, by theshape of the frame 200 at the leaflet attachment region 212 and theleaflet free edge 306, as shown in FIG. 2A. In the embodiments of theprosthetic valve 100 shown in FIGS. 2A-2F, 3A-3F, 4A-4F, and 5, theshape of the leaflet 300, and corresponding leaflet attachment region212 of the frame 200, is substantially that of a parabola. The leaflet300 may define a shape that is predetermined for a particular purpose.FIG. 6A is a perspective view of a prosthetic valve 102 having a frame200 and a plurality of leaflets 300 each having a first leafletcomponent 310 and a second leaflet component 320 defining a shapesubstantially that of an isosceles trapezoid, in accordance with anembodiment. It has been found that leaflets 300 defining a shapesubstantially that of an isosceles trapezoid has improved bendingdynamics as compared to that of a parabola. Improved bending dynamics ofthin, flexible leaflets may include, but are not limited to, reducedcreasing and wrinkling and faster opening and closing response to fluidpressure changes.

FIG. 6B is a perspective view of a prosthetic valve 102 having a frame200 and a plurality of leaflets 300 each having a first leafletcomponent 310 and a second leaflet component 320 defining a shapesubstantially that of an isosceles trapezoid, in accordance with anembodiment. The first overlap region 315 and the second overlap region325 define a leaflet overlap region 335 that tapers in width such thatthere is no overlap adjacent to and a predetermined distance away fromthe frame 200 defining a regurgitant gap 331 of a predetermined size.The regurgitant gap 331 allows a predetermined amount of retrograde flowto pass through the regurgitant gap 331 when the prosthetic valve 102 isclosed. The regurgitant gap 331 is operable to prevent pinching orcreasing of the first outflow free edge 316 and the second inflow freeedge 327 at the frame attachment location adjacent the regurgitant gapwhen the leaflet 300 is in the closed position. Additionally, theregurgitant gap 331 may assist in preventing fluid stagnation at thelocation of the regurgitant gap 331 so at to prevent thrombus formation.

FIG. 7 is a plan view of a frame 200 unrolled to a flat profile tobetter visualize the shape of the frame components, in accordance withthe embodiment of FIG. 6. The frame 200 comprises a leaflet attachmentregion 212 that has substantially the shape of three sides of anisosceles trapezoid having two leaflet attachment sides 223, and aleaflet attachment base 224.

The leaflets 300 comprising the first leaflet component 310 and thesecond leaflet component 320 may be made in a number of different ways.In accordance with an embodiment, each leaflet 300 is made as a singlepair including a first leaflet component 310 and a second leafletcomponent 320. In accordance with another embodiment, as shown in FIG.8, a plurality of leaflets 300, and in particular, a plurality of secondleaflet components 320, may be made from a single leaflet pattern. Byway of example, a leaflet pattern comprising a plurality of leaflets canbe made by starting with a cylinder of biological or synthetic materialand cutting the cylinder into a pattern that defines the leaflets.

FIG. 8 is a plan view of a leaflet pattern 360 comprising a plurality offirst leaflet components 310 and second leaflet components 320, inaccordance with an embodiment. The leaflet pattern 360 may be made froma flat sheet of material cut into a leaflet pattern 360 and subsequentlyrolled into a cylindrical shape or cut from a cylindrical component tocorrespond to the cylindrical shape of the frame 200. In accordance withanother embodiment, the leaflet pattern 360 may be formed is bycompression or injection molding. The second leaflet components 320 maybe linked together via second tabs 364.

Referring to FIG. 8, the first leaflet component 310 comprises a firstframe attachment edge 319 and a first outflow free edge 316. The firstframe attachment edge 319 includes a plurality of first tabs 362 thatcouple to components of the frame 200 in a wrap-around fashion inaccordance with an embodiment, as shown by way of example in FIG. 6. Thesecond leaflet component 320 comprises a second inflow free edge 327, asecond outflow free edge 326, and second frame attachment edges 329. Thesecond frame attachment edge 329 includes a plurality of second tabs 364that couple to components of the frame 200 in a wrap-around fashion.

Although some of the embodiments described herein provide, by way ofexample, attachment edges including tabs that couple to the frame, it isunderstood and appreciated that the leaflets may be coupled to the framein many ways known in the art. By way of example, but not limitedthereto, the leaflets may be coupled to the frame using mechanicalelements, such as, but not limited to, those associated with posts,hooks, and suture, and using other means such as, but not limited to,heat bonding, gluing, molding and crimping. Embodiments presented hereinare not limited by the particular coupling means used to couple theleaflet, and corresponding leaflet components, to the frame or othersupport structure.

As provided above, the shape of the leaflets 300 are defined, at leastin part, by the shape of the frame 200 at the leaflet attachment region212 and the leaflet free edge 306. The shape of the leaflets 300 canalso be defined by the processes used to manufacture the prostheticvalve 100, such as, but not limited, those described below. For example,in accordance with an embodiment, the shape of the leaflets 300 dependsin part on making the leaflets 300 using molding and trimming processesto impart a predetermined shape to the leaflets 300.

FIGS. 9 and 10 are plan views of a leaflet pattern 360 comprising afirst leaflet component 310 and a second leaflet component 320,respectively, in accordance with an embodiment. The first leafletcomponent 310 comprises a first frame attachment edge 319 and a firstoutflow free edge 316. The first frame attachment edge 319 includes aplurality of first tabs 362 that are operable to couple to components ofthe frame 200 adjacent the leaflet attachment base 224 and at least aportion of the two leaflet attachment sides 223, as shown in FIGS. 2A, 6and 7. The first frame attachment edge 319 defines a shape of a portionof the leaflet sides 307 and the leaflet base 308, in that the twoleaflet sides 307 diverge from the leaflet base 308. FIG. 9 shows twoalternative embodiments for the leaflet base 308 in dashed lines, astraight first frame attachment edge 319 a, corresponding to the frame200 of FIG. 7, and a parabolic first frame attachment edge 319 b,suitable for a parabolic leaflet attachment base 224 corresponding tothe frame 200 of FIG. 2A. During the opening and closing of the leaflet300, the first leaflet component 310 will bend about the leaflet base308. Bending about the straight first frame attachment edge 319 a may bein a more controlled manner that may reduce wrinkling and/or flutteringof the first leaflet component 310 as compared with bending about theparabolic first frame attachment edge 319 b.

The second leaflet component 320 comprises a second inflow free edge327, a second outflow free edge 326, and two second frame attachmentedges 329 that diverge from the second inflow free edge 327. The secondframe attachment edges 329 include a plurality of second tabs 364 thatcouple to components of the frame 200 adjacent each of the two leafletattachment sides 223. The first outflow free edge 316 of the firstleaflet component 310 is operable to overlap the second inflow side 322of the second inflow free edge 327 of the second leaflet component 320to define an overlap region 315, as shown in the embodiment of FIG. 6,and similarly for the embodiment of FIG. 2A. The shape of the secondinflow free edge 327 is predetermined by the shape of the first outflowfree edge 316 and the desired width of the overlap region 315, suitablefor a particular purpose.

In accordance with embodiments, as exemplified in FIGS. 2A, 3A, 4A, 5,6A, wherein the second leaflet component 320 has a second inflow freeedge 327 being not coupled to the leaflet attachment base 224 of theframe 200, it has been found that the second leaflet component 320 hasimproved bending dynamics as compared to that of a parabolic leaflet 30such as shown in FIG. 1A. The benefits of improved bending dynamics ofthe leaflet second component 320 may include, but are not limited to,reduced creasing and wrinkling, reduced fluttering, faster opening andclosing response to fluid pressure changes, and an increase indurability.

In the previous embodiments, the first leaflet component 310 and thesecond leaflet component 320 are generally located upstream anddownstream on the frame 200, respectively, defining a single gap 330generally extending across the leaflet 300 perpendicular to the axis Xof the prosthetic valve 100, as shown in FIG. 2F. It may be advantageousto provide a leaflet with more than one gap 330 for a predetermined flowdynamic behind the leaflet.

FIG. 11A is a perspective view a prosthetic valve 600 having a frame 200and a plurality of leaflets 630 each having a plurality of first leafletcomponents 610 that overlap a second inflow side 622 of a second leafletcomponent 620, in accordance with an embodiment. Similarly to theembodiment of FIGS. 2E and 2F, a gap 330 formed between the firstleaflet component 610 and the second leaflet component 620 when theleaflet 630 is not in the closed position allows fluid adjacent thefirst outflow side 614 and the second outflow side 624 to pass throughthe gap 330 during fluid flow in the forward flow direction 402 throughthe lumen 214. That is, the recirculating flow 406 behind the leaflet630 may pass through the gap 330 preventing the recirculating flow 406from slowing down or stagnating behind the leaflet 300. Further, the gap330 also allows fluid flow in the forward flow direction 402 to passthrough the gap 330 from the first inflow side 612 and the second inflowside 622 further disrupting and displacing the recirculating flow 406behind the leaflet 630 to downstream of the leaflet 630. Thus, fluidbehind the leaflet 630 is less likely to clot or form thrombus,particularly at the leaflet base 608 and where it attaches to the frame200. In this embodiment, the first leaflet component 610 comprises amaterial with a high modulus such that it resists bending under theanticipated flow conditions. Since the first leaflet component 610 isnot supported by the second leaflet component 320 at the overlap region625 when in the closed position, the first leaflet component 610 mustresist the back pressure of the fluid when in the closed position toprevent prolapse.

FIGS. 12A and 13 are plan views of a leaflet pattern 660 comprising aplurality of first leaflet components 610 and second leaflet components620, respectively, in accordance with an embodiment. Referring to FIG.12A, each of the first leaflet components 610 comprise a first frameattachment edge 619 and a first outflow free edge 616. The first frameattachment edge 619 includes a plurality of first tabs 662 that coupleto components of the frame 200.

The second leaflet component 620 comprises a plurality of second inflowfree edges 627, a second outflow free edge 626, and three second frameattachment edges 629. The second frame attachment edges 629 include aplurality of first tabs 662 that couple to components of the frame 200.Alignment of each of the first leaflet components 610 relative to thesecond leaflet component 620 is provided by locating first tab apertures611 on first tabs 662 with second tab apertures 621 on second tabs 664.

The leaflets 630 comprise multiple first leaflet components 610, in thisembodiment, two first leaflet components 610, and a second leafletcomponent 620 defining two second inflow free edges 627. The secondleaflet component 620 is coupled to the frame 200 along second frameattachment edges 629. A first leaflet component 610 is coupled to theframe 200 along the first frame attachment edge 619 adjacent each of thesecond inflow free edges 627 so as to define a gap 330 therebetween whenthe leaflet 630 is open. In accordance with an embodiment, the firstoutflow free edge 616 of the first leaflet component 610 is locatedadjacent to and overlaps the second inflow side 622 of the second inflowfree edge 627 to define the overlap region 625. Because of the specificlocation of the gap 330, the gap 330 will close in sealing engagement atthe overlap region 625, shown in FIG. 11B, to prevent regurgitent flowwhen the leaflet 630 is in the closed position.

In accordance with the embodiment of FIG. 11A, the upstream-most secondframe attachment edge 629 a provides additional support to the secondinflow free edges 627 such that they do not prolapse when in the closedposition resisting downstream flow pressure. The length of theupstream-most second frame attachment edge 629 a is sized for aparticular purpose.

FIG. 11B is a perspective view a prosthetic valve 600 having a frame 200and a plurality of leaflets 630 each having a plurality of first leafletcomponents 610 that overlap a second outflow side 624 of a secondleaflet component 620, in accordance with an embodiment. The firstoutflow free edge 616 of the first leaflet component 610 is locatedadjacent to and overlaps with the second outflow side 624 of the secondinflow free edge 627 to define the overlap region 625. The gap 633 willclose in sealing engagement at the overlap region 625 to preventregurgitent flow when the leaflet 630 is in the closed position. FIG.11C is a cross-sectional view along cut-line 110 of the embodiment ofFIG. 11B when the leaflet 630 is in the closed position. FIG. 11D is across-sectional view along cut-line 110 of the embodiment of FIG. 11Bwhen the leaflet 630 is in the open position. A gap 330 formed betweenthe first leaflet component 610 and the second leaflet component 620when the leaflet 630 is not in the closed position allows fluid flow inthe forward flow direction 402 to pass through the gap 330 from thefirst inflow side 612 and the second inflow side 622 disrupting anddisplacing the recirculating flow 406 behind the leaflet 630. Thus,blood behind the leaflet 630 is less likely to clot or form thrombus,particularly at the leaflet base 608 and where it attaches to the frame200. Under certain flow conditions, the gap 330 also allows fluidadjacent the first outflow side 614 and the second outflow side 624 topass through the gap 330 during fluid flow in the forward flow direction402 through the lumen 214. That is, the recirculating flow 406 behindthe leaflet 630 may pass through the gap 330 preventing therecirculating flow 406 from slowing down or stagnating behind theleaflet 630.

FIG. 12B is another embodiment of a first leaflet component 610 that maybe used in cooperation with the second leaflet component 620 of FIG. 13.The first leaflet component 610 comprises two a first frame attachmentedges 619 and two first outflow free edges 616. The first frameattachment edges 619 includes a plurality of first tabs 662 that coupleto components of the frame 200. This embodiment is similar to theembodiment of FIG. 12A wherein the two first leaflet components 610 arecoupled together as one component.

FIG. 12C is another embodiment of a first leaflet component 610 that maybe used in cooperation with the second leaflet component 620 of FIG. 13.This embodiment is similar to the embodiment of FIG. 12B wherein the twofirst leaflet components 610 are coupled together as one component. Thefirst leaflet component 610 comprises two a first frame attachment edges619 and two first outflow free edges 616. The first frame attachmentedges 619 includes a plurality of first tabs 662 that couple tocomponents of the frame 200. The first leaflet component 610 furthercomprises a tether element 640 that couples the two first outflow freeedges 616 to the frame via a plurality of first tabs 662. The tetherelement 640 is operable to prevent prolapse of the two first outflowfree edges 616 when the leaflets are in the closed position.

FIG. 14 is a perspective view a prosthetic valve 700 having a frame 200and a plurality of leaflets 730 each having a plurality of first leafletcomponents 610 that overlap a second leaflet component 620, inaccordance with an embodiment. The second leaflet component 620 has arelatively narrow upstream-most second frame attachment edge 629 aproviding the benefit of providing relatively large gaps between the twofirst leaflet components 610 and the second leaflet component 620 whenthe leaflet is not in the closed position while providing tetheredsupport of the second inflow free edges 627 that prevents prolapse whenin the closed position resisting downstream flow pressure.

FIG. 15 is a perspective view a prosthetic valve 800 having a frame 200and a plurality of leaflets 830 each having one first leaflet component610 that overlaps a second leaflet component 620 that defines two secondinflow free edges 627, in accordance with another embodiment. The secondleaflet component 620 is similar to the embodiment of FIG. 14 in thatthe second leaflet component 620 has a relatively narrow upstream-mostsecond frame attachment edge 629 a providing the benefit of providingrelatively large gaps between the first leaflet component 610 and thesecond leaflet component 620 when the leaflet is not in the closedposition while providing tethered support of the second inflow freeedges 627 that prevents prolapse when in the closed position resistingdownstream flow pressure.

It is appreciated that embodiments of the prosthetic valve having one ormore first leaflet components and one or more second leaflet components,and where the overlap region is on the inflow side or outflow side ofthe second leaflet component, are predetermined for a particular purposeto provide flow through the gap therebetween when the leaflet is in theopen position and to prevent regurgitent flow through the gaptherebetween when the leaflet is in the closed position. The gap formedbetween the first leaflet component and the second leaflet componentwhen the leaflet is not in the closed position allows fluid adjacent thefirst outflow side and the second outflow side to pass through the gapduring fluid flow in the forward direction through the lumen. That is,the recirculating flow behind the leaflet may pass through the gap 330preventing the recirculating flow from slowing down or stagnating behindthe leaflet. Further, the gap also allows forward flow to pass throughthe gap from the first inflow side and the second inflow side furtherdisrupting and displacing the recirculating flow behind the leaflet todownstream of the leaflet. Thus, blood behind the leaflet is less likelyto clot or form thrombus, particularly where the leaflet attaches to theframe.

In accordance with another embodiment, as shown in FIGS. 16A-16F, aprosthetic valve 900 comprises a leaflet 930 having a second leafletcomponent 320 defining a second leaflet aperture 850 therethrough and afirst leaflet component 310 operable to close the second leafletaperture 850 when the leaflet 930 is in the closed position. FIGS. 16Aand 16B are perspective and axial views, respectively, of a prostheticvalve 900 in a closed position, in accordance with an embodiment. FIGS.16C and 16D are perspective and axial views, respectively, of theprosthetic valve 900 in an open position, in accordance with anembodiment. FIGS. 16E and 16F are cross-sectional views of the closedprosthetic valve 900 of FIG. 16B along cutline 16E-16E and of theprosthetic valve 900 of FIG. 16D along cutline 16F-16F, respectively.

As shown in FIG. 16A, a frame 200 is operable to hold and support aplurality of leaflets 930. The frame 200 is annular, that is, it definesa cylinder having a lumen 214 having an axis X and a plurality ofcommissure posts 210 extending parallel to the axis X that are spacedfrom one another. Between the commissure posts 210 is a leafletattachment region 212 that is operable to couple with and support theleaflet 930 about a perimeter of the leaflet 930.

The leaflet 930 includes a first leaflet component 310 and a secondleaflet component 320, in accordance with an embodiment. The firstleaflet component 310 has a first inflow side 312 and a first outflowside 314 opposite the first inflow side 312 that defines a firstthickness. The first leaflet component 310 has a first frame attachmentedge 319 and a first outflow free edge 316. The first leaflet component310 defines a second leaflet aperture 850 adjacent the leaflet base 308.

The second leaflet component 320 has a second inflow side 322 and asecond outflow side 324 opposite the second inflow side 322 defining asecond thickness. The second leaflet component 320 has a plurality ofsecond frame attachment edges 329 and an aperture occluder 382therebetween that is operable to occlude the second leaflet aperture 850when the leaflet 930 is in the closed position. The first leafletcomponent 310 and the second leaflet component 320 are configured to bemovable between an open position to allow fluid flow in a forward flowdirection through the lumen 214 and a closed position in cooperativeengagement that prevents regurgitant flow.

The first leaflet component 310 and the second leaflet component arearranged on the frame 200 such that they at least partially overlap. Asecond overlap region 325 adjacent to the second inflow free edge 327overlaps a first overlap region 315 adjacent to the first outflow freeedge 316 such that a portion of the second inflow side 322 of the secondleaflet component 320 is in contact and in sealing engagement with aportion of the first outflow side 314 of the first leaflet component 310when the leaflet 300 is in the closed position defining a leafletoverlap region 335 operable to prevent regurgitant flow through theleaflet 300 at the leaflet overlap region 335, as shown in FIG. 16E.

During fluid flow in the forward flow direction 402 when the leaflet 930is not in the closed position, as shown in FIG. 16F, when the inflowpressure is greater than the outflow pressure, the first overlap region315 and the second overlap region 325 move away from each other whereinthe first leaflet component 310 uncovers the second leaflet aperture 850allowing fluid to flow therethrough. The second leaflet aperture 850 inthe second leaflet component 320 when the leaflet 300 is not in theclosed position allows fluid adjacent the second inflow side 322 to passthrough the second leaflet aperture 850 when the fluid is moving in theforward flow direction 402 through the lumen 214. The aperture occluder382 to move downstream from the second leaflet aperture 850.Recirculating flow 406 from behind the leaflet 930, including the firstleaflet component 310 may pass in front of the aperture occluder 382 soas to prevent the recirculating flow 406 from stagnating behind theleaflet 930. Thus, blood behind the leaflet 930 is less likely to clotor form thrombus, particularly at the leaflet base 308 and where itattaches to the frame 200.

Leaflet Material

In accordance with some embodiments herein, the leaflet 300 can comprisea biocompatible material that is not of a biological source and that issufficiently compliant and strong for the particular purpose, such as abiocompatible polymer. In accordance with some embodiments, the firstleaflet component 310 and the second leaflet component 320 comprise thesame material and exhibit the same material properties. In accordancewith other embodiments, the first leaflet component 310 has a bendingstiffness that is greater than the second leaflet component 320.Examples of providing a predetermined bending stiffness include, but notlimited to, using a material having a predetermined modulus andproviding a component of predetermined thickness.

In an embodiment, the leaflet 300 comprises a membrane that is combinedwith an elastomer or elastomeric material to form a composite material.In accordance with other embodiments, the biocompatible material thatmakes up the leaflet 300 comprises a biological material, such as, butnot limited to, human, bovine, and pig tissue.

The leaflet 300 can comprise any biocompatible material sufficientlycompliant and flexible, such as a biocompatible polymer. Either one orboth of the first leaflet component 310 and the second leaflet component320 can comprise a membrane that is combined with an elastomer orelastomeric material to form a composite material. The leaflet 300 cancomprise, according to an embodiment, a composite material comprising anexpanded fluoropolymer membrane, which comprises a plurality of spaceswithin a matrix of fibrils, and an elastomeric material. It should beappreciated that multiple types of fluoropolymer membranes and multipletypes of elastomeric materials can be combined to form a compositematerial while remaining within the scope of the present disclosure. Itshould also be appreciated that the elastomeric material can includemultiple elastomers, multiple types of non-elastomeric components, andinclude such things as inorganic fillers, therapeutic agents, radiopaquemarkers, and the like while remaining within the scope of the presentdisclosure.

In accordance with an embodiment, the composite material includes anexpanded fluoropolymer material made from porous ePTFE membrane, forinstance as generally described in U.S. Pat. No. 7,306,729 to Bacino.

The expandable fluoropolymer, used to form the expanded fluoropolymermaterial described, can comprise PTFE homopolymer. In alternativeembodiments, blends of PTFE, expandable modified PTFE and/or expandedcopolymers of PTFE can be used. Non-limiting examples of suitablefluoropolymer materials are described in, for example, U.S. Pat. No.5,708,044, to Branca, U.S. Pat. No. 6,541,589, to Baillie, U.S. Pat. No.7,531,611, to Sabol et al., U.S. patent application Ser. No. 11/906,877,to Ford, and U.S. patent application Ser. No. 12/410,050, to Xu et al.

The expanded fluoropolymer membrane can comprise any suitablemicrostructure, such as pores, for achieving the desired leafletperformance. Other biocompatible polymers which can be suitable for usein leaflet include but are not limited to the groups of urethanes,silicones (organopolysiloxanes), copolymers of silicon-urethane,styrene/isobutylene copolymers, polyisobutylene,polyethylene-co-poly(vinyl acetate), polyester copolymers, nyloncopolymers, fluorinated hydrocarbon polymers and copolymers or mixturesof each of the foregoing.

In accordance with embodiments, the first leaflet component and thesecond leaflet component may be formed of at least one of Polyetherether ketone (PEEK), expanded Polytetrafluoroethylene (ePTFE),Fluorinated ethylene propylene (FEP), copolymers of tetrafluoroethylene(TFE) and perfluoromethyl vinyl ether (PMVE) (TFE-PMVE copolymer),urethanes, polyimides, thermoplastics, thermosets, 3D printable metalsand polymers (stainless steel, titanium, etc.) nylon, or any otherbiocompatible material suitable for long term blood contact that isdimensionally stable, and does not leech contaminates.

Further examples of leaflet construct materials include: wherein theleaflet construct comprises at least one fluoropolymer membrane layer;wherein the leaflet construct comprises a laminate having more than onefluoropolymer membrane layer; wherein the at least one fluoropolymermembrane layer is an expanded fluoropolymer membrane layer; wherein anelastomer, elastomeric, non-elastomer, or a copolymer of TFE-PMVEmaterial is contained within the expanded fluoropolymer membrane layer;wherein the elastomer or elastomeric material comprises perfluoromethylvinyl ether and tetrafluoroethylene; wherein the expanded fluoropolymermembrane layer comprises ePTFE; wherein the leaflet construct comprisesa composite material having at least one fluoropolymer membrane layerhaving a plurality of pores and an elastomer or elastomeric materialpresent in the pores of at least one of the fluoropolymer membranelayers; wherein the composite material comprises fluoropolymer membraneby weight in a range of about 10% to 90%; wherein the elastomercomprises (per)fluoroalkylvinylethers (PAVE); wherein the elastomer orelastomeric material comprises a copolymer of tetrafluoroethylene andperfluoromethyl vinyl ether; wherein the elastomer is silicone; whereinthe elastomer is a fluoroelastomer; wherein the elastomer is a urethane;and wherein the elastomer or elastomeric material is a TFE/PMVEcopolymer; wherein the TFE/PMVE copolymer comprises essentially ofbetween about 40 and 80 weight percent perfluoromethyl vinyl ether andcomplementally 60 and 20 weight percent tetrafluoroethylene; and whereinthe leaflet construct comprises silicone.

The leaflet comprises a section of material, such as a sheet, that isattached to the frame. The leaflet can be formed of any suitablematerial, and need only be biocompatible or be able to be madebiocompatible. The material can advantageously be formed of a flexiblematerial. Examples of suitable materials for the valve leaflet includenatural materials, synthetic materials, and combinations of natural andsynthetic materials. Examples of suitable natural materials includeextracellular matrix (ECM) materials, such as small intestine submucosa(SIS), and other bioremodellable materials, such as bovine pericardium.Other examples of ECM materials that can be used in the prostheticvalves of the invention include stomach submucosa, liver basementmembrane, urinary bladder submucosa, tissue mucosa, and dura mater.Examples of suitable synthetic materials include polymeric materials,such as expanded polytetrafluoroethylene and polyurethane. ECM materialsare particularly well-suited materials for use in the leaflet, at leastbecause of their abilities to remodel and become incorporated intoadjacent tissues. These materials can provide a scaffold onto whichcellular in-growth can occur, eventually allowing the material toremodel into a structure of host cells.

In accordance with an embodiment, the first leaflet component and thesecond leaflet component comprise a porous polymer membrane and anelastomeric material present in pores of the porous polymer membranesuch that the first leaflet component and the second leaflet componentsare impermeable. Further, in another embodiment, the porous polymermembrane is expanded polytetrafluoroethylene. Further, in anotherembodiment, the elastomeric material is an elastomer. Further, inanother embodiment, the elastomeric material is TFE/PMVE copolymer.Further, in another embodiment, the elastomer is TFE/PMVE copolymer.

In accordance with an embodiment, the first leaflet component and thesecond leaflet component comprise a porous polymer membrane and anelastomer present in pores of the porous polymer membrane such that thefirst leaflet component and the second leaflet components areimpermeable. Further, in another embodiment, the porous polymer membraneis expanded polytetrafluoroethylene. Further, in another embodiment, theelastomer is TFE/PMVE copolymer.

In accordance with an embodiment, the first leaflet component or thesecond leaflet component comprise a porous polymer membrane and anelastomeric material present in pores of the porous polymer membranesuch that the first leaflet component or the second leaflet component,respectively, is impermeable.

In accordance with an embodiment, the first leaflet component and thesecond leaflet component comprise expanded polytetrafluoroethylenemembrane and TFE/PMVE copolymer present in pores of the expandedpolytetrafluoroethylene membrane such that the first leaflet componentand the second leaflet component, respectively, are impermeable.

In accordance with an embodiment, at least one of the first leafletcomponent and the second leaflet component comprise a biological tissue.

In accordance with an embodiment, a prosthetic valve comprises a frameand a plurality of leaflets each including one or more first valvecomponents that overlap a second valve component. The frame includes aninflow end and an outflow end and leaflet attachment portions. Eachfirst leaflet component includes a first inflow end portion and a firstoutflow end portion wherein the first inflow end portion is coupled to aleaflet attachment portion adjacent the inflow end of the frame. Thesecond leaflet portion has a second inflow end portion, a second outflowend portion, a plurality of side attachment portions, a lumen facingside and a frame facing side. At least two side attachment portions arecoupled to the leaflet attachment portions of the frame. A portion ofthe first leaflet outflow end portion overlaps with a portion of thesecond leaflet inflow end portion of the leaflet on the lumen facingside defining an overlap region. The leaflet being movable between anopen position to allow fluid flow in a forward direction through thelumen and a closed position in cooperative engagement with the valvecomponent in sealing engagement at the overlap region that preventsfluid flow in a retrograde direction through the frame. A gap is formedbetween the overlap region to allow fluid flow therethrough during fluidflow in a forward direction through the frame.

In accordance with another embodiment, a prosthetic valve comprises afirst leaflet component and a second leaflet component. The secondleaflet component being disposed downstream of the first leafletcomponent. The first leaflet component and the second leaflet componentare in operable engagement configured to allow forward fluid flowthrough the prosthetic valve in a first direction extending downstreamand prevent retrograde fluid flow through the prosthetic valve in anopposite direction extending upstream, and in operable engagementconfigured to allow fluid flow between a gap defined by the firstleaflet component and the second leaflet component during forward fluidflow through the prosthetic valve.

In accordance with another embodiment, a prosthetic valve comprises aframe and a leaflet component coupled to the frame being moveablebetween a first position that permits fluid to forward flow in a firstdirection through the prosthetic valve and a second position thathinders retrograde flow in a second direction opposite the firstdirection through the prosthetic valve. The leaflet component includes ameans for opening an aperture during forward flow to enable fluid flowtherethrough during forward flow and to close the aperture duringretrograde flow.

In accordance with another embodiment, a prosthetic valve, comprises aframe and a leaflet coupled to the frame being moveable between a firstposition that permits antegrade flow through the prosthetic valve and asecond position that prevents retrograde flow through the prostheticvalve. The leaflet component includes a recirculation aperture operableto open to enable recirculation flow therethrough during antegrade flowthrough the prosthetic valve and operable to close to prevent retrogradeflow therethrough through the prosthetic valve.

In accordance with another embodiment, a prosthetic valve comprises aframe, a first leaflet component coupled to the frame, and a secondleaflet component coupled to the frame and at least partiallyoverlapping the first leaflet component defining an overlap region. Thesecond leaflet component being moveable between a first position thatbrings the first leaflet component and the second leaflet component intosealing engagement at the overlap region that prevents retrograde flowthrough the prosthetic valve and moveable between a second position thatallows antegrade flow through the prosthetic valve and separates thefirst leaflet component and the second leaflet component at the overlapregion defining a recirculation aperture that allows recirculation flowthrough the recirculation aperture.

In accordance with another embodiment, a prosthetic valve comprises aframe and at least one leaflet. The frame has an inflow end and anoutflow end opposite the inflow end and defining a lumen therebetweendefining an axis, the frame having at least one leaflet attachmentregion having an inflow portion and an outflow portion. A leaflet iscoupled to each of the at least one leaflet attachment regions. Eachleaflet includes at least one first leaflet component and a secondleaflet component. Each first leaflet component has a first inflow sideand a first outflow side opposite the first inflow side, a first frameattachment edge and a first outflow free edge. The second leafletcomponent has a second inflow side and a second outflow side oppositethe second inflow side. The second leaflet component has a plurality ofsecond frame attachment edges, at least one second inflow free edge anda second outflow free edge opposite the at least one second inflow freeedge. The second leaflet component being movable between an openposition to allow fluid flow in a forward direction through the lumenand a closed position in cooperative engagement with the at least onefirst leaflet component that prevents fluid flow in a retrogradedirection through the lumen. The first frame attachment edge of the atleast one first leaflet component being coupled to the inflow portion ofthe leaflet attachment region with the first inflow side facing theaxis. The frame attachment edges of the second leaflet component beingcoupled to at least the outflow portion of the leaflet attachment regionwith the second inflow side facing the axis. Wherein a second overlapregion of the second inflow free edge overlaps a first overlap region ofthe first outflow free edge of the at least one first leaflet componentwhen the leaflet is in the closed position defining a leaflet overlapregion preventing fluid flow through the lumen in the retrogradedirection. Wherein the first overlap region of the at least one firstleaflet component and the second overlap region are not in contacttherewith wherein the first outflow free edge of the at least one firstleaflet component and the second inflow free edge define a gaptherebetween when the leaflet is not in the closed position, whereinfluid adjacent the second outflow side can pass through the gap duringfluid flow in the forward direction.

In accordance with another embodiment, a prosthetic valve comprises aframe and a plurality of leaflets. The frame has an inflow end and anoutflow end opposite the inflow end and defines a lumen therebetweendefining an axis. The frame has at least one leaflet attachment regionhaving an inflow portion and an outflow portion. Each leaflet beingcoupled to each of the at least one leaflet attachment regions. The atleast one leaflet includes at least one first leaflet component and asecond leaflet component. The at least one first leaflet component has afirst inflow side and a first outflow side opposite the first inflowside. The at least one first leaflet component has a first frameattachment edge and a first outflow free edge, The second leafletcomponent has a second inflow side and a second outflow side oppositethe second inflow side. The second leaflet component has a plurality ofsecond frame attachment edges, at least one second inflow free edge anda second outflow free edge opposite the at least one second inflow freeedge. The second leaflet component being movable between an openposition to allow fluid flow in a forward direction through the lumenand a closed position in cooperative engagement with the at least onefirst leaflet component that prevents fluid flow in a retrogradedirection through the lumen. The first frame attachment edge of eachfirst leaflet component being coupled to the inflow portion of theleaflet attachment region with the first inflow side facing the axis.The frame attachment edges of the second leaflet component being coupledto at least the outflow portion of the leaflet attachment region withthe second inflow side facing the axis. Wherein a second overlap regionof the second leaflet component adjacent the second inflow free edgeoverlaps a first overlap region of the first leaflet component adjacentthe first outflow free edge such that they are in sealing engagementtherewith when the leaflet is in the closed position defining a leafletoverlap region preventing fluid flow through the lumen in the retrogradedirection. Wherein the first overlap region of each first leafletcomponent and the second overlap region are not in contact therewithwherein the first outflow free edge of the each of the first leafletcomponent and the second inflow free edge define a gap therebetween whenthe leaflet is not in the closed position, wherein fluid adjacent thesecond outflow side can pass through the gap during fluid flow in theforward direction.

In accordance with embodiments, the valve may comprise the followingproperties, singularly or in combination.

The leaflet may comprise a means for allowing a flow or exchange offluid between the front and back of the leaflet when the leaflet is notin the closed position. Said flow or exchange of fluid may be throughthe leaflet via an aperture, gap or separation of portions of theleaflet. Said aperture, gap or separation may be operable to close toprevent flow of exchange of fluid between the back and the front of theleaflet, when the leaflet is in the closed position.

The valve may comprise a support structure, such as a frame or aconduit; wherein the leaflet is coupled to the support structure.

The leaflet may include a first leaflet component and a second leafletcomponent.

The first leaflet component and the second leaflet component may becoupled to the support structure.

The first leaflet component may be upstream of the second leafletcomponent.

The first leaflet component may be downstream of the second leafletcomponent.

Said flow or exchange of fluid may be via an aperture, gap or separationof the first and second components, when the leaflet is not in theclosed position.

In some embodiments, the second leaflet component comprises an inflowfree edge, and defines a gap between the second leaflet component andthe support structure. In some embodiments, the first leaflet componentor the second leaflet component defines an aperture therethrough, andwherein the other of the first leaflet component or the second leafletcomponent is operable to occlude the aperture.

The first leaflet component and the second leaflet component may bepartially overlapping.

Respective first and second overlap regions of the first leafletcomponent and the second leaflet component may be in sealing engagementwith one another, when the leaflet is in the closed position. The firstleaflet component may comprise a first overlap region and the secondleaflet component may comprise a second overlap region, wherein thefirst and second overlap regions together define a leaflet overlapregion, when the first and second leaflet components are in sealingengagement with one another.

The first and second overlap regions may extend from a free edge of therespective leaflet component.

The first overlap region may extend from, and typically upstream from,an outflow free edge. The second overlap region may extend from, andtypically downstream from, an inflow free edge.

The first and second leaflet components may be brought into sealingengagement with one another by fluid pressure, under the action ofretrograde flow.

The first leaflet component may be stationary relative to the secondleaflet component, or vice versa. The first leaflet component, or thesecond leaflet component may be relatively stationary relative to thesupport structure.

The first leaflet component may be configured to move more slowly thanthe second leaflet component, or vice versa. In some embodiments, thefirst leaflet component is downstream of the second leaflet componentand the second leaflet component is configured to move more slowly thanthe first leaflet component. In some embodiments the first leafletcomponent is upstream of the second leaflet component and the firstleaflet component is configured to move more slowly than the secondleaflet component.

In some embodiments, the first leaflet component may have a higher, or alower, bending stiffness than the second leaflet component.

The first leaflet component may comprise apertures in the first overlapregion. In some embodiments, the second leaflet component may compriseapertures in the second overlap region. During forward flow (i.e.downstream flow) the apertures in the first or second overlap region mayprovide, at least in part, that the respective first or second leafletcomponent moves to the open position at a slower rate than the othersaid leaflet component, such that a gap is formed therebetween.

In some embodiments, apertures are provided in the first or secondoverlap regions to augment regurgitant blood flow. In some embodiments,the leaflet component configured to move more slowly is provided withapertures in its overlap region. In some embodiments, the leafletcomponent configured to move more quickly is provided with apertures inits overlap region.

The apertures in the first or second overlap region may be sealed by theother said overlap region, during retrograde blood flow when the leafletis in the closed position.

The leaflet overlap region may be of any suitable shape orconfiguration. In some embodiments, the leaflet overlap regions tapersin width towards the support structure. For example, in some embodimentsthere is no overlap at and optionally to a predetermined distance awayfrom the support structure.

In some embodiments, when the leaflet is in the closed position, thereis a regurgitant gap or gaps of a predetermined size between the firstand second leaflet components, for example extending away from thesupport structure. The regurgitant gap or gaps allow a predeterminedamount of retrograde flow to pass therethrough, when the valve isclosed.

The relative sizes of the first and second leaflet components maydetermine the axial location of the leaflet overlap region.

The leaflet may provide for flow or exchange of fluid may be viamultiple (e.g. two, or three or more) apertures, gaps or separations,when the leaflet is not in the closed position.

The leaflet may comprise multiple first leaflet components. The leafletmay comprise a first leaflet component comprising multiple outflow freeedges.

In some embodiments, the second leaflet component may comprise multipleinflow free edges, defining multiple gaps between the second leafletcomponent and the support structure, corresponding to one of the saidmultiple first leaflet components or free edges.

In some embodiments, the second leaflet component defines multipleapertures therethrough. The first leaflet component may be operable toocclude the apertures, or one of the said multiple first leafletcomponents may be operable to occlude each said aperture.

Where there are multiple outflow free edges (either of multiple firstleaflet components or of a first leaflet component having multipleoutflow free edges), the leaflet may comprise a tether element, whichcouples said outflow free edges. The tether element may preventprolapse.

The leaflet may comprises a porous polymer membrane and a materialpresent in pores of the porous polymer membrane such that the or eachleaflet is impermeable.

The porous polymer membrane may for example be a fluoropolymer such asexpanded polytetrafluoroethylene, or may be a polymer such aspolyethylene.

The material present in the pores may be an elastomer or an elastomericmaterial or may be a non-elastomeric material. The material present inthe pores may be a TFE/PMVE copolymer.

The leaflet may alternatively or in addition comprise a biologicaltissue, such as native valve tissue, or porcine tissue.

Where the valve comprises one or more first leaflet components and asecond leaflet component, the or each first leaflet component and/or thesecond leaflet component may comprise said porous polymer membrane and amaterial present in pores of the porous polymer membrane such that theor each first leaflet component and/or the second leaflet component isimpermeable.

In some embodiments, wherein at least one of the first leaflet component(or components) and the second leaflet component comprises a biologicaltissue.

The leaflet may have any suitable shape or configuration. For example,the shape of the leaflet, and of a corresponding attachment region to asupport structure, may be generally that of a parabola or of anisosceles trapezoid.

The valve may comprise a plurality of leaflets, for example twoleaflets, three leaflets or four leaflets. The valve may comprise threeleaflets.

Each leaflet may comprise a leaflet free edge. The leaflet free edgesmay coapt under the influence of outflow (i.e. retrograde) fluidpressure; thereby closing the valve.

The valve may be a prosthetic valve. The valve may be a prosthetic heartvalve.

The valve may comprise a leaflet including a first leaflet component anda second leaflet component being disposed downstream of the firstleaflet component, the first leaflet component and the second leafletcomponent are in operable engagement configured to allow forward fluidflow through the prosthetic valve in a first direction extendingdownstream and prevent regurgitant fluid flow through the prostheticvalve in an opposite direction extending upstream, and in operableengagement configured to allow fluid flow between a gap defined by thefirst leaflet component and the second leaflet component during forwardfluid flow through the prosthetic valve.

The valve may comprise a frame; and a leaflet including a first leafletcomponent coupled to the frame and a second leaflet component coupled tothe frame and at least partially overlapping the first leaflet componentdefining an overlap region, the second leaflet component being moveablebetween a first position that brings the first leaflet component and thesecond leaflet component into sealing engagement at the overlap regionthat prevents regurgitant flow through the prosthetic valve and moveablebetween a second position that allows antegrade flow through theprosthetic valve and separates the first leaflet component and thesecond leaflet component at the overlap region defining a recirculationaperture that allows recirculation flow through the recirculationaperture.

The valve may comprise a frame; and a leaflet including a leafletcomponent coupled to the frame being moveable between a first positionthat permits fluid to forward flow in a first direction through theprosthetic valve and a second position that hinders regurgitant flow ina second direction opposite the first direction through the prostheticvalve, the leaflet component including a means for opening an apertureduring forward flow to enable fluid flow therethrough during forwardflow and to close the aperture during retrograde flow.

The valve may comprise a frame; and a leaflet coupled to the frame beingmoveable between a first position that permits antegrade flow throughthe prosthetic valve and a second position that prevents regurgitantflow through the prosthetic valve, the leaflet including a recirculationaperture operable to open to enable recirculation flow therethroughduring antegrade flow through the prosthetic valve and operable to closeto prevent retrograde flow therethrough through the prosthetic valve.

A method for treating a human patient with a diagnosed condition ordisease associated with valve insufficiency or valve failure of a nativevalve, the method comprising implanting a prosthetic valve at thelocation of the native valve. The prosthetic valve comprises a frame anda plurality of leaflets. The frame has an inflow end and an outflow endopposite the inflow end and defines a lumen therebetween defining anaxis. The frame has at least one leaflet attachment region having aninflow portion and an outflow portion. Each leaflet being coupled toeach of the at least one leaflet attachment regions. The at least oneleaflet includes at least one first leaflet component and a secondleaflet component. The at least one first leaflet component has a firstinflow side and a first outflow side opposite the first inflow side. Theat least one first leaflet component has a first frame attachment edgeand a first outflow free edge, The second leaflet component has a secondinflow side and a second outflow side opposite the second inflow side.The second leaflet component has a plurality of second frame attachmentedges, at least one second inflow free edge and a second outflow freeedge opposite the at least one second inflow free edge. The secondleaflet component being movable between an open position to allow fluidflow in a forward direction through the lumen and a closed position incooperative engagement with the at least one first leaflet componentthat prevents fluid flow in a retrograde direction through the lumen.The first frame attachment edge of each first leaflet component beingcoupled to the inflow portion of the leaflet attachment region with thefirst inflow side facing the axis. The frame attachment edges of thesecond leaflet component being coupled to at least the outflow portionof the leaflet attachment region with the second inflow side facing theaxis. Wherein a second overlap region of the second leaflet componentadjacent the second inflow free edge overlaps a first overlap region ofthe first leaflet component adjacent the first outflow free edge suchthat they are in sealing engagement therewith when the leaflet is in theclosed position defining a leaflet overlap region preventing fluid flowthrough the lumen in the retrograde direction. Wherein the first overlapregion of each first leaflet component and the second overlap region arenot in contact therewith wherein the first outflow free edge of the eachof the first leaflet component and the second inflow free edge define agap therebetween when the leaflet is not in the closed position, whereinfluid adjacent the second outflow side can pass through the gap duringfluid flow in the forward direction.

A method for reducing incidents of thrombus or reducing thrombusformation associated with treating a human patient with a diagnosedcondition or disease associated with valve insufficiency or valvefailure of a native valve, the method comprising implanting a prostheticvalve at the location of the native valve. The prosthetic valvecomprises a frame and a plurality of leaflets. The frame has an inflowend and an outflow end opposite the inflow end and defines a lumentherebetween defining an axis. The frame has at least one leafletattachment region having an inflow portion and an outflow portion. Eachleaflet being coupled to each of the at least one leaflet attachmentregions. The at least one leaflet includes at least one first leafletcomponent and a second leaflet component. The at least one first leafletcomponent has a first inflow side and a first outflow side opposite thefirst inflow side. The at least one first leaflet component has a firstframe attachment edge and a first outflow free edge, The second leafletcomponent has a second inflow side and a second outflow side oppositethe second inflow side. The second leaflet component has a plurality ofsecond frame attachment edges, at least one second inflow free edge anda second outflow free edge opposite the at least one second inflow freeedge. The second leaflet component being movable between an openposition to allow fluid flow in a forward direction through the lumenand a closed position in cooperative engagement with the at least onefirst leaflet component that prevents fluid flow in a retrogradedirection through the lumen. The first frame attachment edge of eachfirst leaflet component being coupled to the inflow portion of theleaflet attachment region with the first inflow side facing the axis.The frame attachment edges of the second leaflet component being coupledto at least the outflow portion of the leaflet attachment region withthe second inflow side facing the axis. Wherein a second overlap regionof the second leaflet component adjacent the second inflow free edgeoverlaps a first overlap region of the first leaflet component adjacentthe first outflow free edge such that they are in sealing engagementtherewith when the leaflet is in the closed position defining a leafletoverlap region preventing fluid flow through the lumen in the retrogradedirection. Wherein the first overlap region of each first leafletcomponent and the second overlap region are not in contact therewithwherein the first outflow free edge of the each of the first leafletcomponent and the second inflow free edge define a gap therebetween whenthe leaflet is not in the closed position, wherein fluid adjacent thesecond outflow side can pass through the gap during fluid flow in theforward direction.

Applications

The prosthetic valve of the embodiments provided herein can be used as aprosthetic heart valve. In this capacity, the prosthetic valve is placedin an orifice collocated with a native heart valve or in place of anexcised heart valve to regulate the flow of blood through the heart. Itis believed that the leaflet moves to the first position, for example,as illustrated in FIG. 2B, during systole in which the heart forcesblood through the artery or vein in a forward flow direction 402. Duringdiastole, the leaflet 300 moves to the closed position, illustrated inFIG. 2A, to substantially prevent fluid flow in the second, oppositedirection referred to as retrograde flow. It is believed that a pressurechange and reversal of flow direction occurs during the change fromsystole to diastole, and the leaflet 300 changes position in response tothese changes.

The prosthetic valve of the embodiments provided herein can also be usedas a prosthetic venous valve. In this capacity, the prosthetic valve isplaced in a vein to regulate the flow of blood through the vein.

In accordance with an embodiment, a method of making a prosthetic valvecomprises obtaining a leaflet frame, and a leaflet including a firstleaflet component and a second leaflet component. Coupling the firstleaflet component adjacent to an inlet portion of the leaflet frame.Coupling the second leaflet component adjacent to an outlet portion ofthe leaflet frame such that a second overlap region of a second inflowfree edge of the second leaflet component overlaps a first overlapregion of a first outflow free edge of the first leaflet component suchthat a portion of a second inflow side of the second leaflet componentis in contact and in sealing engagement with a portion of a firstoutflow side of the first leaflet component when the leaflet is in aclosed position defining a leaflet overlap region preventing fluid flowthrough the lumen in the retrograde direction. And wherein the firstoverlap region and the second overlap region are not in contacttherewith wherein the first outflow free edge and the second inflow freeedge define a gap therebetween when the leaflet is not in the closedposition, wherein fluid adjacent the second outflow side can passthrough the gap during fluid flow in the forward direction.

Numerous characteristics and advantages have been set forth in thepreceding description, including various alternatives together withdetails of the structure and function of the devices and/or methods. Thedisclosure is intended as illustrative only and as such is not intendedto be exhaustive. It will be evident to those skilled in the art thatvarious modifications can be made, especially in matters of structure,materials, elements, components, shape, size and arrangement of partsincluding combinations within the principles of the disclosure, to thefull extent indicated by the broad, general meaning of the terms inwhich the appended claims are expressed. To the extent that thesevarious modifications do not depart from the spirit and scope of theappended claims, they are intended to be encompassed therein.

What is claimed:
 1. A prosthetic valve, comprising: a leaflet moveablebetween an open position that permits antegrade flow through theprosthetic valve and a closed position that prevents regurgitant flowthrough the prosthetic valve, the leaflet having an aperture or gap, ora separation of portions of the leaflet to allow a flow or exchange offluid between a front and back of the leaflet, when the leaflet is notin the closed position.
 2. The prosthetic valve of claim 1, wherein theaperture, gap or separation is operable to close to prevent flow ofexchange of fluid between the back and the front of the leaflet, whenthe leaflet is in the closed position.
 3. The prosthetic valve of 2,further comprising a support structure, wherein the leaflet is coupledto the support structure.
 4. The prosthetic valve of claim 3, whereinthe leaflet includes a first leaflet component and a second leafletcomponent.
 5. The prosthetic valve of claim 4, wherein the first leafletcomponent is upstream of the second leaflet component, or wherein thefirst leaflet component is downstream of the second leaflet component.6. The prosthetic valve of claim 5, wherein the flow or exchange offluid is via an aperture, gap or separation of the first and secondcomponents when the leaflet is not in the closed position.
 7. Theprosthetic valve of claim 6, wherein the second leaflet componentcomprises an inflow free edge and defines a gap between the secondleaflet component and the support structure.
 8. The prosthetic valve ofclaim 7, wherein the first leaflet component or the second leafletcomponent defines an aperture therethrough, and wherein the other of thefirst leaflet component or the second leaflet component is operable toocclude the aperture.
 9. The prosthetic valve of claim 8, wherein thefirst leaflet component and the second leaflet component partiallyoverlap.
 10. The prosthetic valve of claim 9, wherein the first leafletcomponent comprises a first overlap region and the second leafletcomponent comprises a second overlap region, wherein the first andsecond overlap regions are in sealing engagement with one another whenthe leaflet is in the closed position.
 11. The prosthetic valve of claim10, wherein the first and second overlap regions each extend from a freeedge of the respective first and second leaflet component.
 12. Theprosthetic valve of claim 11, wherein the first overlap region extendsfrom an outflow free edge of the first leaflet component and the secondoverlap region extends from an inflow free edge of the second leafletcomponent.
 13. The prosthetic valve of claim 11, wherein the firstleaflet component comprises apertures in the first overlap region, orwherein the second leaflet component comprises apertures in the secondoverlap region.
 14. The prosthetic valve of claim 13, wherein the firstleaflet component has a higher bending stiffness than the second leafletcomponent.
 15. The prosthetic valve of claim 12, wherein the first andsecond leaflet components overlap and define an overlap region whichtapers in width towards the support structure.
 16. The prosthetic valveof claim 15, wherein when the leaflet is in the closed position, thereis a regurgitant gap or gaps of a predetermined size between the firstand second leaflet components, extending away from the supportstructure.
 17. The prosthetic valve of claim 1, wherein the leafletcomprises multiple apertures, gaps or separations of portions of theleaflet, to allow a flow or exchange of fluid between the front and backof the leaflet, when the leaflet is not in the closed position.
 18. Theprosthetic valve of claim 3, wherein a shape of the leaflet and theshape of a corresponding attachment region to a support structure isgenerally that of a parabola or of an isosceles trapezoid.
 19. Theprosthetic valve of claim 1, wherein the leaflet comprises a porouspolymer membrane and a material present in pores of the porous polymermembrane such that the leaflet is impermeable.
 20. The prosthetic valveof claim 19, wherein the porous polymer membrane is expandedpolytetrafluoroethylene.
 21. The prosthetic valve of claim 20, whereinthe material present in the pores is an elastomer or an elastomericmaterial or a non-elastomeric material.
 22. The prosthetic valve ofclaim 20, wherein the material present in the pores is a TFE/PMVEcopolymer.
 23. The prosthetic valve of any preceding claim, wherein theleaflet comprises a biological tissue.
 24. A prosthetic valve,comprising: a leaflet including a first leaflet component and a secondleaflet component being disposed downstream of the first leafletcomponent, the first leaflet component and the second leaflet componentare in operable engagement configured to allow forward fluid flowthrough the prosthetic valve in a first direction extending downstreamand prevent regurgitant fluid flow through the prosthetic valve in anopposite direction extending upstream, and in operable engagementconfigured to allow fluid flow between a gap defined by the firstleaflet component and the second leaflet component during forward fluidflow through the prosthetic valve.
 25. A method of making a prostheticvalve, comprising: obtaining a leaflet frame, obtaining a leafletincluding a first leaflet component and a second leaflet component;coupling the first leaflet component adjacent to an inlet portion of theleaflet frame; and coupling the second leaflet component adjacent to anoutlet portion of the leaflet frame such that a second overlap region ofa second inflow free edge of the second leaflet component overlaps afirst overlap region of a first outflow free edge of the first leafletcomponent such that a portion of a second inflow side of the secondleaflet component is in contact and in sealing engagement with a portionof a first outflow side of the first leaflet component when the leafletis in a closed position defining a leaflet overlap region preventingfluid flow through a lumen in a retrograde direction, and wherein thefirst overlap region and the second overlap region are not in contacttherewith wherein the first outflow free edge and the second inflow freeedge define a gap therebetween when the leaflet is not in the closedposition, wherein fluid adjacent a second outflow side can pass throughthe gap during fluid flow in a forward direction.
 26. A method fortreating a human patient with a diagnosed condition or diseaseassociated with valve insufficiency or valve failure of a native valve,the method comprising implanting at or adjacent to a location of thenative valve a prosthetic valve comprising a leaflet moveable between anopen position that permits antegrade flow through the prosthetic valveand a closed position that prevents regurgitant flow through theprosthetic valve, the leaflet having an aperture or gap, or a separationof portions of the leaflet to allow a flow or exchange of fluid betweenthe front and back of the leaflet, when the leaflet is not in the closedposition.
 27. A method for reducing incidents of thrombus or reducingthrombus formation associated with treating a human patient with adiagnosed condition or disease associated with valve insufficiency orvalve failure of a native valve, the method comprising implanting at oradjacent to a location of the native valve a prosthetic valve comprisinga leaflet moveable between an open position that permits antegrade flowthrough the prosthetic valve and a closed position that preventsregurgitant flow through the prosthetic valve, the leaflet having anaperture or gap, or a separation of portions of the leaflet to allow aflow or exchange of fluid between the front and back of the leaflet,when the leaflet is not in the closed position.